Updates to Counter-Strike: Source and the Source Engine, along with some improvements to SourceTV have been released. The updates will be applied automatically when your Steam client is restarted. The specific changes include:

Counter-Strike: Source:

Added beta for Counter-Strike: Source Dynamic Weapon Pricing

Source Engine:

Exclude .lua files from being downloaded by clients

Exclude the addons/, gamemods/ and lua/ from having files inside of them downloaded to clients (Garry's MOD support)